Men With Sedentary Lifestyles Have Lower Sperm Count: A study done on 189 men found that those who watched more than 20 hours of television a week had a 44% lower sperm count than men who watched almost no television. In contrast, “Men who engaged in moderate to vigorous exercise for 15 or more hours a week had a 73% higher sperm count than men who exercised less than five hours per week.” However, although a reduced sperm count may indicate lower fertility, a lower number of available sperm “does not absolutely prevent men from fathering a child,” authors said.